This is a polar map of permafrost extent in the Northern Hemisphere. A sidebar explains how permafrost, as it forms and later thaws, serves as both a sink and source for carbon to the atmosphere. Related multimedia is a slideshow of permafrost scientists from U. of Alaska, Fairbanks, collecting permafrost data in the field.

In this audio slideshow, an ecologist from the University of Florida describes the radiocarbon dating technique that scientists use to determine the amount of carbon within the permafrost of the Arctic tundra. Understanding the rate of carbon released as permafrost thaws is necessary to understand how this positive feedback mechanism is contributing to climate change that may further increase global surface temperatures.

This well-designed experiment compares CO2 impacts on salt water and fresh water. In a short demonstration, students examine how distilled water (i.e., pure water without any dissolved ions or compounds) and seawater are affected differently by increasing carbon dioxide in the air.

This video addresses acidification of the ocean and the ecological and economic implications of the resulting pH change on marine life. It includes information about how ocean acidification resulting from increased absorption of CO2 from the atmosphere is affecting ocean species such as sea urchins and oysters. Scientists from the University of California at Santa Barbara discuss their experiments with sea creatures in acidic sea water. There is an associated lesson plan and classroom activity that has students test the effects of CO2 on water pH.

This static image from NOAA's Pacific Marine Environmental Laboratory Carbon Program offers a visually compelling and scientifically sound image of the sea water carbonate chemistry process that leads to ocean acidification and impedes calcification.

This activity covers the role that the oceans may play in climate change and how climate change may affect the oceans. It is lesson 8 in a nine-lesson module Visualizing and Understanding the Science of Climate Change.

In this experiment, students investigate the importance of carbon dioxide to the reproductive growth of a marine microalga, Dunalliela sp. (Note that the directions are for teachers and that students protocol sheets will need to be created by teachers.)

In this activity, students conduct a short hands-on demonstration that simulates ocean acidification resulting from excess atmospheric carbon dioxide and discuss potential implications of increases in ocean temperatures and acidification due to climate change.